Filters: Tags: Fertilizer (X) > Types: Citation (X)
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This dataset consists of a series of rasters covering the conterminous United States. Each raster is a one kilometer (km) grid for 18 selected Census of Agriculture statistics mapped to land use pixels for the time period 1950 to 2012. A supplemental set of 9 statistics mapped at the entire county level are also provided as 1-km rasters. The rasters are posted as ArcGIS grids. The statistics represent values for crops, livestock, irrigation, fertilizer, and manure usage. Most statistics are mapped for all 14 Census of Agriculture reporting years in that time frame: 1950, 1954, 1959, 1964, 1969, 1974, 1978, 1982, 1987, 1992, 1997, 2002, 2007, and 2012.
Categories: Data;
Types: Citation;
Tags: Census of Agriculture,
Conterminous U.S.,
Cropland,
Crops,
Dasymetric mapping,
This paper contrasts the natural and anthropogenic controls on the conversion of unreactive N2 to more reactive forms of nitrogen (Nr). A variety of data sets are used to construct global N budgets for 1860 and the early 1990s and to make projections for the global N budget in 2050. Regional N budgets for Asia, North America, and other major regions for the early 1990s, as well as the marine N budget, are presented to Highlight the dominant fluxes of nitrogen in each region. Important findings are that human activities increasingly dominate the N budget at the global and at most regional scales, the terrestrial and open ocean N budgets are essentially disconnected, and the fixed forms of N are accumulating in most...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Biogeochemistry,
Denitrification,
Fertilizer,
Fossil fuel combustion,
Haber-Bosch,
These data are a subset of categories and items from county-level data for the conterminous United States covering the census reporting years beginning with the 1950 Census of Agriculture and ending with the 2012 Census of Agriculture. Historical (1950-1997) data were extracted from digital files obtained through the Intra-university Consortium on Political and Social Research (ICPSR). More current (1997-2012) data were extracted from the National Agriculture Statistical Service(NASS) Census Query Tool for the census years of 1997, 2002, 2007, and 2012. Please refer to the Supplemental Information element of the metadata for information on the Census of Agriculture, the Inter-university Consortium for Political...
Categories: Data;
Types: Citation;
Tags: Census of Agriculture,
Conterminous United States,
County-level Census of Agriculture,
Crop production,
Cropland,
Effects of annual additions of mineral N and P (100 kg ha-1) on plant species composition and annual aboveground net primary production (ANPP) were investigated during the first three years following disturbance in a semi-arid ecosystem. Additions of N reduced richness of perennial plant species during years 2 and 3, while P reduced the number of perennial species only in year 3. From year 1 to year 2, annual and biennial species richness declined in all treatments while ANPP of annual species increased greatly. Added N increased ANPP of annual species while it decreased ANPP of most perennial species relative to the unfertilized control treatment. Community similarities were higher for the control and native vegetation...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Plant and Soil,
Springer Netherlands,
disturbance,
fertilizer,
nitrogen,
This product consists of 29 datasets of tabular data and associated metadata for watershed characteristics of 1,530 study sites of the Surface Water Trends (SWT) project of the U.S. Geological Survey’s (USGS) National Water Quality Program (NWQP). The project is conducting national studies of trends in water quality of streams and rivers for periods ranging from 10 to 40 years, between 1972 and 2012. The data here include both static and time-series characteristics. Static data include primarily physical characteristics which have changed little over this period, such as geology, soils, and topography. Time-series data represent characteristics which may or may not have changed over time, such as land use, agricultural...
Categories: Data;
Types: Citation;
Tags: Atmospheric Deposition,
Basin Morphology,
Census of Agriculture,
Conterminous US,
Crop Practices,
In the absence of human activities, biological N fixation is the primary source of reactive N, providing about 90–130 Tg N year−1 (Tg = 1012 g) on the continents. Human activities have resulted in the fixation of an additional 150 Tg N year−1 by energy production, fertilizer production, and cultivation of crops (e.g., legumes, rice). Some sinks of anthropogenic N have been estimated (e.g., N2O accumulation in the atmosphere; loss to coastal oceans), however due to the uncertainty around the magnitude of other sinks (e.g., retention in groundwater, soils, or vegetation or denitrification to N2) a possibly large portion of the N fixed by humans is missing. While we know that N is accumulating in the environment,...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Asia,
Environmental Pollution,
Nitrogen,
fertilizer,
food production,
This data set contains county-level estimates of nitrogen and phosphorus from fertilizer, for both farm and nonfarm uses, for the conterminous United States, for 1987 through 2012. State-level farm and nonfarm nitrogen and phosphorus were derived from the Association of American Plant Food Control Officials (AAPFCO) commercial fertilizer sales data. State estimates were then allocated to the county-level using fertilizer expenditure from the Census of Agriculture as county weights for farm fertilizer, and effective population density as county weights for nonfarm fertilizer. Data computations for 2007 - 2012 estimates are results of methods applied directly from Gronberg and Spahr, 2012. Data for 1987 - 2006 are...
Categories: Data;
Types: Citation;
Tags: Agricultural,
Conterminous United States,
Ecology,
Farm,
Fertilizer,
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